Cristiano Nunes Nesi

Efeito de um suplemento mineral traço e vitaminas A e E injetáveis sobre a produção e composição de leite em vacas Holandesas

The purpose of this research was to evaluate the use of mineral traces (Copper, Zinc, Selenium, and Manganese), as well as vitamins A and E in injectable forms on the production and composition of Dutch cow milk at the end of the transitional period, until after 60 days of lactation. 31 females were divided into two experimental groups: the treated grou p (n= 15) that received mineral supplements (10 mg of Copper, 40 mg of Zinc, 5 mg of Selenium, and 10 mg of Manganese) and vitamins (175 mg of vitamin A and 250 mg of vitamin E) and injections (5 mL minerals trace solution and 5 mL vitamin solution subcutaneously). After 225 gestation days, 255 pregnancy days and the estimated day of delivery, the control group (n = 16) that received injections of the sterilizing solution (5 mL dosage from a subcutaneous via) on the same days as the treated group. Milk samples were collected on the 7th, 14th and 21st days after birth, which were used to evaluate the production, the quality (colostrum), and composition (fat, lactose, protein, nonfat dry extract, total solids, urea, and somatic cell count (SCC)). The initial and minimum values estimated by the model indicated that there was not a difference in milk production and SCC levels between the groups. Among the remaining milk components, only the urea showed significant differences between treated and untreated groups (p= 0.002). Also, there were no significant differences observed in the quality of the colostrum. This leads us to believe that the use of injectable solutions containing Cu, Zn, Se, Mn and vitamins A and E have no effect on the composition of urea in the milk, and also showed no effect on SCC and other milk components, as well as in production. However, more studies should be performed.

Mancha branca no milho: etiologia e controle

A mancha branca, que tem a bacteria Pantoea ananatis como principal agente etiologico, alem de especies fungicas associadas, como Phaeosphaeria maydis , e uma doenca que vem causando reducoes na produtividade do milho, podendo chegar ate 60% quando sao utilizados hibridos sujeitos a condicoes favoraveis para a doenca. Este trabalho tem como objetivo apresentar informacoes sobre a mancha branca e suas principais tecnicas de manejo. Entre tais tecnicas, destacam-se os controles genetico, cultural e quimico, sendo este ultimo o mais utilizado, com enfase na aplicacao do grupo das estrobilurinas, por apresentar os melhores resultados. The White spot (WS), which has the bacterium Pantoea ananatis as the main pathogen, associated with fungal species, like Phaeosphaeria maydis , is a disease that has been causing reductions in the maize yield. Losses can reach up to 60% when susceptible hybrids are used and conditions for the disease are favorable. This study aims to present some information about WS and main control methods. Among the control methods recommended, genetic, cultural and chemical control stand out, but fungicides are the most used tool, highlighting the strobilurin group because it presents the best results.

Superação de dormência em sementes de Jatobá avaliadas por análise de sobrevivência

This work evaluated methods of overcoming dormancy in Jatoba seeds (Hymenaea courbaril L.) by utilizing survival analysis. 75 seeds per treatment were evaluated: without treatment (T1), immersion in water at outdoor temperature for 120 h (T2) and 72 h (T3), immersion in water at 90 oC and rest in the same water for 24 h (T4), mechanical scarification (T5) and mechanical scarification and soaking it in water for 24 h (T6). The seeds germinated per treatment were registered daily. The Kaplan-Meier method was utilized to estimate the curves of survival and median periods for the germination, the log-rank test and the Cox semiparametric model to estimate the effect of the treatments. The median periods of germination were 56 days (T4) and 33 days (T6). The seeds submitted to T4, T5 and T6 have respectively 22.5, 4.7 and 3.7 times higher capacity to germinate (shorter period for germination) than those seeds that were not submitted to overcoming dormancy.

Produtividade, incidência de podridões de colmo e qualidade de grãos de milho cultivados sob diferentes arranjos espaciais e densidades de plantas

The productivity and quality of maize can be influenced by the occurrence of diseases. The intensity is affected by environmental factors and phytotechnical practices. Thus, this study was carried out to evaluate the effect of arrangement of plants and plant density on grain yield and thousand grain weight and incidence of stalk rot and fungi associated with grains. The work was conducted during the 2010/2011 and 2012/2013 seasons in Chapeco, SC, Brazil. The treatments consisted of different row spacings (0.45 and 0.80 m) and plant densities (50, 60, 70, 80 and 90 thousand plants ha-1) with a design of randomized blocks in subdivided sub plots. In the main plot two simple hybrids of corn early cycle were tested (P30F53H and DKB 240H), the subplots and the spacing in the sub-subplot plant populations. The experimental units consisted of six lines of 4 m in length. The yield on the 0.45 m spacing was 29.65% higher than in the 0.80 m spacing for the studied hybrids. The mass of a thousand grains and the incidence of rot grains decreased with an increase in plant population. However, the incidence of Fusarium verticillioides, Fusarium graminearum and Stenocarpella maydis was not affected by plant populations or by spacing tested under the conditions of this study.